问

AL从元数据中设置经度和纬度

渊博的蓝天大海_210 发布于 2023-01-19 12:14

iphone

Iphone应用程序,我需要从图像中提取经度和纬度,到目前为止所有工作,除了获取gps数据.我在imagePickerController中有这个代码:

- (UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{
    NSURL *referenceURL = [info objectForKey:UIImagePickerControllerReferenceURL];
    ALAssetsLibrary *library1 = [[ALAssetsLibrary alloc] init];
    [library assetForURL:referenceURL resultBlock:^(ALAsset *asset) {
        ALAssetRepresentation *rep = [asset defaultRepresentation];
        NSDictionary *metadata = rep.metadata;
        NSLog(@"%@", metadata);

        CGImageRef iref = [rep fullScreenImage] ;

        if (iref) {
            self.myPicture.image = [UIImage imageWithCGImage:iref];
        }
    } failureBlock:^(NSError *error) {
        // error handling
    }];
}

这输出:

...
     Sharpness = 2;
    ShutterSpeedValue = "9.710661431591664";
    SubjectArea =         (
        1295,
        967,
        699,
        696
    );
    WhiteBalance = 0;
};
"{GPS}" =     {
    Altitude = "144.8338028169014";
    AltitudeRef = 0;
    DateStamp = "2013:09:07";
    ImgDirection = "243.4423676012461";
    ImgDirectionRef = T;
    Latitude = "37.97166666666666";
    LatitudeRef = N;
    Longitude = "23.72733333333333";
    LongitudeRef = E;
    TimeStamp = "08:10:30";
};
.....

我怎样才能获得经度和纬度并放入NSString？谢谢

1 个回答

使用CLLocation *location = [myasset valueForProperty:ALAssetPropertyLocation];可以帮助您从拍摄的照片中获取纬度和长度检查以下代码并使用您的要求.

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {

    NSLog(@"url %@",info);


    if ([picker sourceType] == UIImagePickerControllerSourceTypePhotoLibrary) {

        // Get the asset url
        NSURL *url = [info objectForKey:@"UIImagePickerControllerReferenceURL"];
        NSLog(@"url %@",url);
        // We need to use blocks. This block will handle the ALAsset that's returned:
        ALAssetsLibraryAssetForURLResultBlock resultblock = ^(ALAsset *myasset)
        {
            // Get the location property from the asset


            CLLocation *location = [myasset valueForProperty:ALAssetPropertyLocation];
            // I found that the easiest way is to send the location to another method

            self.lat =location.coordinate.latitude; //[[gpsdata valueForKey:@"Latitude"]floatValue];
            self.lng =location.coordinate.longitude;
            NSLog(@"\nLatitude: %f\nLongitude: %f",self.lat,self.lng);

            strLocation=[NSString stringWithFormat:@"La:%f Lo%f",self.lat,self.lng];

            NSLog(@"Can not get asset - %@",strLocation);


        };
        // This block will handle errors:
        ALAssetsLibraryAccessFailureBlock failureblock  = ^(NSError *myerror)
        {
            NSLog(@"Can not get asset - %@",[myerror localizedDescription]);
            // Do something to handle the error
        };



        ALAssetsLibrary* assetslibrary = [[ALAssetsLibrary alloc] init];
        [assetslibrary assetForURL:url
                       resultBlock:resultblock
                      failureBlock:failureblock];



    }


    [self dismissViewControllerAnimated:YES completion:^{

            }];

}

2023-01-19 12:16 回答

天之蓝

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